Toxic emissions produced by internal combustion engines are the subject of environmental concern and have prompted increasingly stringent emissions regulations by the government. Toxic emissions produced by diesel engines, for example, include hydrocarbons, nitrogen oxides, carbon monoxide, and particulate matter. Although most of these exhaust emissions have been reduced in many modern engines, NOx and particulate matter remain at relatively high levels. To reduce these toxic emissions and comply with governmental regulations, a number of exhaust aftertreatment components, including particulate filters and catalytic converters, have been developed. According to specific examples, an engine system may include a diesel particular filter, a diesel oxidation catalyst, and a selective catalytic reduction component for treating the engine exhaust.
U.S. Patent Application Publication No. 2013/0213013 to Mitchell et al. discloses a sensor module for sensing characteristics of a fluid flowing through a fluid conduit. The sensor module includes a sample probe with at least one sample arm that extends radially inwardly from a sidewall portion of the fluid conduit to a center portion of the fluid conduit, defines a fluid flow channel and includes a plurality of inlet apertures. The sample probe also includes a fluid well, with a sensor positioned in an interior volume of the fluid well.
As should be appreciated, there is a continuing need to reduce exhaust emissions using effective and efficient means. The present disclosure is directed to such an endeavor.